A set of important mathematical model codes, which have been developed over the years, are sometimes categorized as river basin model codes. These may be used for determining long term water sharing and allocation arrangements or operational river basin planning. River basin model codes are relatively simple network-oriented codes, representing relevant water transfers and storage operations based on the spatial and temporal variation in water availability and water demand. These models enable authorities to better understand the impacts of different water allocation scenarios and operational regimes and their corresponding benefits, and to evaluate the trade-offs between water releases made for competing sectors.

(GWP 2013b)